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IEEE 802.15.4 is a new standard uniquely designed for low‐rate wireless sensor networks (WSNs). It targets low data rate, low power consumption and low‐cost wireless networking, and offers device level wireless connectivity. The purpose of this paper is to propose a traffic adaptive power control algorithm for beacon relayed distributed WSNs.

A general coordinated sleeping algorithm and the traffic adaptive algorithm are combined in an IEEE 802.15.4 MAC protocol to achieve high‐energy efficiency and high performance at the same time.

By observing the sporadic traffic and beacon relaying characteristics of WSNs, the paper proposes a traffic‐adaptive IEEE 802.15.4 MAC with a coordinated sleeping algorithm. Based on various performance studies, it was found that the proposed algorithm can significantly improve power consumptions in wireless sensor networks.

The paper is of value in proposing a traffic adaptive power control algorithm showing highly efficient power consumptions in low‐traffic conditions as well as with an acceptable degree of adaptation to high‐traffic conditions. In delay performance, it shows longer delay performance compared with other schemes because of the beacon relay procedure while the proposed algorithm reduces the power consumptions dramatically.

Cross-layer approach in media access control (MAC) layer will address interference and jamming problems. Hybrid distributed MAC can be used for simultaneous voice, data transmissions in wireless sensor network (WSN) and Internet of Things (IoT) applications. Choosing the correct objective function in Nash equilibrium for game theory will address fairness index and resource allocation to the nodes. Game theory optimization for distributed may increase the network performance. The purpose of this study is to survey the various operations that can be carried out using distributive and adaptive MAC protocol. Hill climbing distributed MAC does not need a central coordination system and location-based transmission with neighbor awareness reduces transmission power.

Distributed MAC in wireless networks is used to address the challenges like network lifetime, reduced energy consumption and for improving delay performance. In this paper, a survey is made on various cooperative communications in MAC protocols, optimization techniques used to improve MAC performance in various applications and mathematical approaches involved in game theory optimization for MAC protocol.

Spatial reuse of channel improved by 3%–29%, and multichannel improves throughput by 8% using distributed MAC protocol. Nash equilibrium is found to perform well, which focuses on energy utility in the network by individual players. Fuzzy logic improves channel selection by 17% and secondary users’ involvement by 8%. Cross-layer approach in MAC layer will address interference and jamming problems. Hybrid distributed MAC can be used for simultaneous voice, data transmissions in WSN and IoT applications. Cross-layer and cooperative communication give energy savings of 27% and reduces hop distance by 4.7%. Choosing the correct objective function in Nash equilibrium for game theory will address fairness index and resource allocation to the nodes.

Other optimization techniques can be applied for WSN to analyze the performance.

Game theory optimization for distributed may increase the network performance. Optimal cuckoo search improves throughput by 90% and reduces delay by 91%. Stochastic approaches detect 80% attacks even in 90% malicious nodes.

Channel allocations in centralized or static manner must be based on traffic demands whether dynamic traffic or fluctuated traffic. Usage of multimedia devices also increased which in turn increased the demand for high throughput. Cochannel interference keep on changing or mitigations occur which can be handled by proper resource allocations. Network survival is by efficient usage of valid patis in the network by avoiding transmission failures and time slots’ effective usage.

Literature survey is carried out to find the methods which give better performance.

This paper proposes a distributed multi‐channel MAC protocol which is an extension of our early work GRID [1]. GRID is characterized by the following features: (i) it integrates a location‐aware channel assignment, (ii) it follows an “on‐demand” style to access the medium, (iii) the number of channels required is independent of the network topology, and (iv) no form of clock synchronization is required. The proposed protocol wants to further improve the GRID in two parts. First, we propose a fully distributed medium access mechanism without using a single control channel such that all of the network traffic can be distributed evenly over all data channels. Therefore, the network throughput will be increased significantly. Second, we can set the more suitable transmission range and GRID size by considering the factors of host density and packet arrival rate of the network within an specified area. Thus, all of channels will be reused more efficiently than GRID. Simulation results show that the throughput of our protocol is superior to GRID and IEEE 802.11.

In this paper, the design of multiple channels to achieve the goal of a high‐performance medium access control (MAC) protocol is to be proposed to solve the problem of wasting bandwidth resources due to waiting for the backoff time.

In the MAC design of this paper, a control channel and a data channel are used to improve bandwidth utilization. When the control channel waits for the backoff time, the data channel may transfer data. As a result, bandwidth utilization can be improved. In order to have better bandwidth utilization in multiple channels, the authors also propose a bandwidth allocation strategy for control channels and data channels. According to the strategy, the control and data signals can be smoothly transmitted without blocking or waiting, thereby not wasting bandwidth resources. Finally, the authors propose multiple control sub‐channels and data sub‐channels to further reduce the backoff time penalty and make more communication pairs work in a transmission range to increase the throughput.

The paper solves the following problems bandwidth waste that results from waiting for the backoff time in the single channel model and bandwidth allocation strategy for the control and data sub‐channels in the multiple channel model to achieve throughput enhancement in mobile ad‐hoc networks.

The proposed method needs the support of multiple channels.

From the result, the bandwidth allocation ratio of the proposed method performs better than other various allocation ratios. In addition, the proposed method with the bandwidth allocation strategy and multiple data and control sub‐channels results in a better throughput than IEEE 802.11 DCF by 22.3 per cent.

The proposed method using multiple control and data sub‐channels can improve the throughput and reduce bandwidth waste over IEEE 802.11 DCF.

The energy optimization techniques developed for conventional ad hoc networks do not appropriately address the unique features of the wireless embedded sensor networks (WESNs). In the WESN environment, only reducing the overall energy consumption is not considered enough to maximize the life span of the entire network, but maintaining full network connectivity for a sufficiently long period of time is also an important design goal due to the energy constraints of each node. The wireless radio is a major energy user and is often the focus of energy conservation mechanisms, since the nodes communicate in a shared medium (air interface). The medium access control (MAC) layer of the communication protocol stack arbitrates access to the communications link by manipulating the sleep, listen, transmit, and receive states of the radio transceivers. The bursty traffic networks experience long periods of inactivity interrupted by unplanned and often short lived periods of high traffic loads. Currently available MAC protocols cannot meet application fidelity requirements of the bursty traffic networks since they are designed either for networks with periodic traffic or are not sufficiently traffic-adaptive, thereby introducing large multi-hop latency delays to realize network connectivity, overprovision during light traffic conditions, and slow ramp up at the initiation of a high traffic episode. This paper presents enhancements made to the energy efficient MAC protocol which is especially designed for the bursty traffic networks and in the process targets some available communication techniques used in the WESNs for discussion and comparison.

Ad hoc mobile networks are commonplace in every aspect of our everyday life. They become essential in many industries and have uses in logistics, science and the military. However, because they operate mostly in open spaces, they are exposed to a variety of dangers. The purpose of this study is to introduce a novel method for detecting the MAC layer misbehavior.

The proposed novel approach is based on exponential smoothing for throughput prediction to address this MAC layer misbehavior. The real and expected throughput are processed using an exponential smoothing algorithm to identify this attack, and if these metrics exhibit a trending pattern, an alarm is then sent.

The effect of the IEEE 802.11 MAC layer misbehavior on throughput was examined using the NS-2 network simulator, as well as the approval of our novel strategy. The authors have found that a smoothing factor value that is near to 0 provides a very accurate throughput forecast that takes into consideration the recent history of the updated values of the real value. As for the smoothing factor values that are near to 1, they are used to identify MAC layer misbehavior.

According to the authors’ modest knowledge, this new scheme has not been proposed in the state of the art for the detection of greedy behavior in mobile ad hoc networks.

Many synchronization approaches are based on low-level time capturing, causing a tight integration with the Media Access Control (MAC) layer. Alternatively, this study aims to present a hybrid approach combining both receiver–receiver and sender–receiver schemes to reduce the variation of two-way message exchange durations, in heavy-load networks. To achieve network-wide synchronization, a variant of Prim’s algorithm (Cormen et al., 2009) is used to build a spanning tree, guaranteeing the minimum number of ancestors and limited error propagation. The simulation results show that the proposed approach is very competitive with a set of the most-cited synchronization protocols. In addition, a new synchronization simulator SynSim was developed using C++ language

To achieve network-wide synchronization, a variant of Prim's algorithm (Cormen et al., 2009) is used to build a spanning tree, guaranteeing the minimum number of ancestors and limited error propagation.

Simulation results show that the proposed approach is very competitive with a set of the most-cited synchronization protocols. In addition, a new synchronization simulator SynSim was developed using in C++ language.

It can be concluded from the experiments that MDSP is suitable for WSNs especially if MAC layer timestamping is not possible. So, the mean delays synchronization protocol (MSDP) is suitable to achieve time synchronization in single-hop and multi-hop networks without the MAC layer timestamping in large wireless sensor network (WSN) deployments.

A future enhancement of MDSP could be switching between the traditional timestamping and the new proposed timestamping based on a given threshold, which is the number of nodes in the neighborhood and the load of the network. It will be also interesting to test it in a prototype. The proposed solution can be used in practice to implement the Time-division multiple access (TDMA) protocol in a WSN. In addition, the proposed simulator can be used in a computer network synchronization protocols course.

To the best of authors’ knowledge, this study’s contribution is original. In addition, the authors implemented a new synchronization simulator

In multihop wireless networks, the number of neighbors has an important role in the network performance since links are dynamically formed between a node and its neighbors. This paper aims to investigate this issue.

The paper quantitatively studies the effects of the average number of neighbors in multihop wireless networks on the network connectivity, the number of hops needed to traverse a certain distance, which can be used to determine the hop diameter of a network, and the total energy consumed by packet transmission, which can be used to choose an optimum average number of neighbors that minimizes the energy consumption. This paper also presents an analysis of the energy consumption that can be applied to a wide range of access protocols and show the effect of a variety of factors.

Results show that the minimum average number of neighbors to guarantee the overall network connectivity depends on the size of a network coverage. There is a sharp knee in the network connectivity with decrease of the average number of neighbors, N. If the distance between a source and destination, d, is known, the number of hops needed to reach the destination is usually between d/R∼2d/R, where R is the transmission range. A larger average number of neighbors N leads to a smaller number of hops to traverse a certain distance, which in turn results in a smaller traffic load caused by relaying packets. However, a bigger N also causes more collisions when a contention medium access scheme is used, which leads to more energy consumed by packet transmission. The results show that the optimum N which minimizes the energy is obtained by balancing several factors affecting the energy.

The paper provides a useful study on the effects of the number of neighbors in multihop wireless networks.

Internet of Things (IoT) is an up-and-coming conception that intends to link multiple devices with each other. The aim of this study is to provide a significant analysis of Green IoT. The IoT devices sense, gather and send out significant data from their ambiance. This exchange of huge data among billions of devices demands enormous energy. Green IoT visualizes the concept of minimizing the energy consumption of IoT devices and keeping the environment safe.

This paper attempts to analyze diverse techniques associated with energy-efficient protocols in green IoT pertaining to machine-to-machine (M2M) communication. Here, it reviews 73 research papers and states a significant analysis. Initially, the analysis focuses on different contributions related to green energy constraints, especially energy efficiency, and different hierarchical routing protocols. Moreover, the contributions of different optimization algorithms in different state-of-the-art works are also observed and reviewed. Later the performance measures computed in entire contributions along with the energy constraints are also checked to validate the effectiveness of entire contributions. As the number of contributions to energy-efficient protocols in IoT is low, the research gap will focus on the development of intelligent energy-efficient protocols to build up green IoT.

The analysis was mainly focused on the green energy constraints and the different robust protocols and also gives information on a few powerful optimization algorithms. The parameters considered by the previous research works for improving the performance were also analyzed in this paper to get an idea for future works. Finally, the paper gives some brief description of the research gaps and challenges for future consideration that helps during the development of an energy-efficient green IoT pertaining to M2M communication.

To the best of the authors’ knowledge, this is the first work that reviews 65 research papers and states the significant analysis of green IoT.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.